Rotor blade locking assembly

Abstract

A rotor blade locking assembly for locking a rotor blade in a deployed position. The rotor blade locking assembly comprises a locking mechanism configured to be coupled to a blade grip. The locking mechanism comprises a latch and an actuator configured to cause the latch to move between an unlocked position and a locked position. The assembly comprises a locking plate configured to be coupled to the rotor blade. The locking plate comprises a bearing surface configured to bear against a contact surface of the latch, when the latch is in the locked position.

What is claimed is: 
     
       1. A rotor blade locking assembly, comprising:
 a locking mechanism configured to be coupled to a blade grip, the locking mechanism comprising:
 a latch having a contact surface; and 
 an actuator configured to cause movement of the latch between an unlocked position and a locked position; and 
 
 a locking plate configured to be coupled to a rotor blade, the locking plate having a bearing surface configured to bear against the contact surface of the latch when the latch is in the locked position; 
 wherein a substantially tubular wall of the blade is selectively captured between the latch and the blade grip. 
 
     
     
       2. The rotor blade locking assembly of  claim 1 , wherein the locking mechanism further comprises a housing that receives at least a portion of the latch therein. 
     
     
       3. The rotor blade locking assembly of  claim 2 , wherein the latch is configured to linearly translate along a locking axis between the locked position and the unlocked position. 
     
     
       4. The rotor blade locking assembly of  claim 3 , wherein the locking mechanism further comprises a linkage coupled between the actuator and the latch, the linkage being configured to prevent linear translation of the latch from the locked position to the unlocked position without input from the actuator. 
     
     
       5. The rotor blade locking assembly of  claim 4 , wherein the bearing surface of the locking plate and/or the contact surface of the latch are configured to cause a pre-load force between the latch and the locking plate when the latch is translated from the unlocked position to the locked position. 
     
     
       6. The rotor blade locking assembly of  claim 5 , wherein the linkage comprises:
 a crank slider coupled to the actuator; 
 a pre-load link rotatably coupled to the latch about a latch-link axis; and 
 a bell crank having a first arm slidably coupled to the crank slider and a second arm rotatably coupled to the pre-load link about an arm-link axis, the bell crank being configured to rotate relative to the housing about a crank axis. 
 
     
     
       7. The rotor blade locking assembly of  claim 6 , wherein the latch-link axis, the arm-link axis, and the crank axis are substantially parallel to each other, and when the latch is in the locked position, the locking axis is generally perpendicular to, and intersects each of, the latch-link axis, the arm-link axis, and the crank axis. 
     
     
       8. A rotor blade assembly, comprising:
 a blade grip configured to be rotatably coupled to a rotor hub about a pitch-change axis; 
 a locking mechanism coupled to the blade grip, the locking mechanism comprising:
 a latch having a contact surface; and 
 an actuator configured to cause movement of the latch between an unlocked position and a locked position; 
 
 a rotor blade rotatably coupled to the blade grip about a blade-fold axis; and 
 a locking plate coupled to the rotor blade, the locking plate having a bearing surface configured to bear against the contact surface of the latch when the latch is in the locked position; 
 wherein a substantially tubular wall of the blade is selectively captured between the latch and the blade grip. 
 
     
     
       9. The rotor blade assembly of  claim 8 , wherein the locking mechanism is coupled to an exterior surface of the blade grip and the locking plate is coupled to an exterior surface of the rotor blade. 
     
     
       10. The rotor blade assembly of  claim 9 , wherein the rotor blade comprises a generally C-shaped portion that extends beyond the blade-fold axis, the C-shaped portion having an interior surface configured to contact the exterior surface of the blade grip. 
     
     
       11. The rotor blade assembly of  claim 10 , wherein the latch is configured to linearly translate along a locking axis between the locked position and the unlocked position, the locking axis being generally parallel to the pitch-change axis. 
     
     
       12. The rotor blade assembly of  claim 11 , further comprising:
 a blade bolt having a blade-fold motor disposed at least partially therein, the blade-fold motor being configured to rotate the rotor blade, about the blade-fold axis, between a folded position and a deployed position. 
 
     
     
       13. The rotor blade assembly of  claim 12 , wherein a spar of the rotor blade extends into the C-shaped portion. 
     
     
       14. The rotor blade assembly of  claim 13 , wherein the exterior surface of the blade grip and the interior surface of the C-shaped portion include buffer materials where they are in contact each other. 
     
     
       15. A rotorcraft, comprising:
 a fuselage; and 
 a rotor assembly, comprising:
 a rotor hub having an arm; and 
 a rotor blade assembly, comprising:
 a blade grip rotatably coupled to the arm of the rotor hub about a pitch-change axis; 
 a rotor blade rotatably coupled to the blade grip about a blade-fold axis; and 
 a locking mechanism coupled to the blade grip, the locking mechanism comprising:
 a latch having a contact surface; 
 an actuator configured to cause movement of the latch between an unlocked position and a locked position; and 
 
 a locking plate coupled to the rotor blade, the locking plate having a bearing surface configured to bear against the contact surface of the latch when the latch is in the locked position; 
 wherein a substantially tubular wall of the blade is selectively captured between the latch and the blade grip. 
 
 
 
     
     
       16. The rotorcraft of  claim 15 , wherein the rotor blade comprises a generally C-shaped portion that extends beyond the blade-fold axis, the C-shaped portion having an interior surface configured to contact an exterior surface of the blade grip. 
     
     
       17. The rotorcraft of  claim 16 , wherein the locking mechanism is coupled to the exterior surface of the blade grip and the locking plate is coupled to an exterior surface of the C-shaped portion of the rotor blade. 
     
     
       18. The rotorcraft of  claim 17 , further comprising:
 a blade bolt having a blade-fold motor disposed at least partially therein, the blade-fold motor being configured to rotate the rotor blade, about the blade-fold axis, between a folded position and a deployed position. 
 
     
     
       19. The rotorcraft of  claim 18 , wherein the latch is configured to linearly translate along a locking axis between the locked position and the unlocked position, the locking axis being generally parallel to the pitch-change axis. 
     
     
       20. The rotorcraft of  claim 19 , wherein the bearing surface of the locking plate and/or the contact surface of the latch are configured to cause a pre-load force between the latch and the locking plate when the latch is translated from the unlocked position to the locked position.